Unable to compute taylor expansion using taylortool

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Im trying to use taylortool but keep getting "cant compute taylor expansion", and I think it is because my function has decimal points.
If f(x) does not have a decimal point, it works fine, even with fractions like (1/4*x*cos(x)).

Accepted Answer

VBBV
VBBV on 12 Dec 2022
Edited: VBBV on 12 Dec 2022
Since you are using a Edit box to read the function, it returns a string expression
A = 1.176*x*cos(x); % A is variable to read the input function entered
str2sym(A) % convert to string function to symbolic expression and try
An example shown below works fine
syms x
f = 1.176*x*cos(x);
T6 = taylor(f,x)
T6 = 
  2 Comments
VBBV
VBBV on 12 Dec 2022
I think it may be due to the order used for the expression to evaluate the expansion
syms x
f = 1.176*x*cos(x);
T6 = taylor(f,x,'Order',1) % this might be reason
T6 = 
0
syms x
f = 1.176*x*cos(x);
T6 = taylor(f,x,'Order',2)
T6 = 
Torsten
Torsten on 12 Dec 2022
@Rafael comment moved here:
To make my function work, my f(x) is 1176/1000*x*cos(x), but I think it's weird that 1.176 doesn't work

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